This invention relates to concrete construction and, more particularly, to an improved apparatus for providing a hole through a poured concrete structure.
With one type of structural construction, concrete or the like is poured between one or more forms defining various surfaces of the structure. For example, a vertical concrete wall is generally poured between two spaced-apart, vertically arranged forms. Further, in new construction, whether commercial, residential, or industrial, in the formation of concrete walls or the like, it is commonly necessary to provide a relatively large number of accurately located and shaped through-holes or openings to permit various types of utilities to pass through the finished structure, for example, communications and power wiring, plumbing, gas, etc.
It is also desirable to be able to form and maintain such openings through the structure in a relatively simple manner which does not interfere with the formation of the structure. Normally, a plastic or metal sleeve is installed between the forms prior to the pouring of concrete. End flanges or clips at the ends of the sleeve are attached to the concrete forms to preclude movement of the sleeve relative to the forms. In one application, the sleeve has a length equal to the thickness of the wall; and the ends of the sleeve terminate with flanges that are an integral part of the sleeve. The flanges are attached to a concrete form with fasteners such as nails or screws. The fixed, nonflexible flanges are particularly difficult to use when concrete forms are not parallel or have a nonflat surface such as that created by an angled or beveled surface.
In another application, several clips are attached to each end of a straight sleeve in the installation process; and the clips are mounted to the concrete forms with fasteners such as nails or screws. While the clips work reasonably well under ideal conditions, such conditions rarely exist. For example, concrete forms are placed and assembled to rough dimensions and therefore, are not always parallel. With nonparallel forms, it is difficult to initially, properly install the screws holding the clips to the form. Further, if the clips are not properly secured they may become dislodged during the pouring process; and an end of the sleeve is allowed to float in the pour. The end of the sleeve may separate from the form allowing concrete to fill the void between the end of the sleeve and the form and also fill the sleeve. In other situations, the concrete forms may maintain parallelism but lose their verticality. In order to maintain the sleeve generally horizontal, the ends of the sleeve must be mitered at an angle that matches the nonvertical forms. Thus, the installation of the sleeve is more complex and time consuming. In further situations, the clips are difficult to use where the sleeve must be mounted over multiple surfaces of a form, for example, a flat surface and a beveled surface.
Thus, the imprecision and variations in the installation and assembly of the concrete forms and any movement of the forms during the pouring and setting processes often cause significant problems in the installation of sleeves to form through-holes in the walls. Those problems often result in a substantial increase in the time and effort required to install the sleeves and may adversely impact the reliability of the sleeve in forming a through-hole in the wall. Any failure of the sleeve or the attaching clips, requires additional labor to fix any defects in the resulting through-hole. Thus, while a sleeve appears to be a simple device to form a hole in a concrete wall, in practice, there are many conditions that unpredictably add substantial time and cost.
Consequently, there is a need for an improved apparatus for forming through-holes in molded structures such as concrete walls.
The present invention provides an apparatus for forming through-holes in concrete structures that is simple and quick to install, reliable in use and durable over the useful life of the structure. Using the apparatus of the present invention, through-holes can be formed with a variety of sleeving materials that are commonly found on a construction site. The apparatus of the present invention is especially useful in those applications where sidewalls of the concrete forms are skewed and nonparallel. Thus, the apparatus of the present invention permits through-hole cores to be quickly installed without creating special parts for nonparallel form walls. Further, the apparatus of the present invention is firmly securable on a variety of surfaces and thus, is stable during the pouring and curing process. In addition, the apparatus of the present invention has a knockout end cap that permits conduit, pipes and other utilities to be quickly run.
According to the principles of the present invention and in accordance with the preferred embodiments, the invention provides an apparatus for receiving one end of a utility conduit sleeve within a form. The apparatus has a tubular body with an interior surface intersecting first and second ends. The tubular body receives one end of the sleeve through one end and has a flexible flange at its opposite end. The flexible flange is securable against an inside surface of the form. A breakable, thin cover extends over the opposite end of the tubular body to prevent material from entering the tubular body during a pouring process.
In one aspect of the invention, the tubular body is also made of a flexible material, and the cover is easily breakable or penetrable with a knife or other tool.
These and other objects and advantages of the present invention will become more readily apparent during the following detailed description taken in conjunction with the drawings herein.